Constant tension paper supply mechanism

ABSTRACT

A paper supply mechanism especially adapted for supplying pressure sensitive adhesive backed label material, which supply mechanism includes a constant tension means comprising a selfadjusting brake which compensates for loss of paper roll mass, and a tension indicating means.

United States Patent Gerald J. Ottavan Ridgefield, NJ. Appl. No. 736,768

[72] Inventor [56] References Cited UNITED STATES PATENTS 5/1932 Armbrecht...................

' 3,398;914 8/1968 Cunningham Primary Examiner-Nathan L. Mintz Attorney-Hubbell, Cohen and Stiefel [22] Filed June 13,1968 [45] Patented Mar. 2, 1971 [73] Assignee Allamatic Corporation Clifi'side Park, NJ.

[54] CONSTANT TENSION PAPER SUPPLY MECHANISM ABSTRACT: A paper supply mechanism especially adapted for supplying pressure sensitive adhesive backed label material, which supply mechanism includes a constant tension means comprising a self-adjusting brake which compensates for loss of paper roll mass, and a tension indicating means.

3 2 N46 N771 2-H 4 2M2 .ma W: F m: g m: .m m: w m: I D WWW 3 m m w m "S 1L0 h W d C 5mm 6 UIF 1]] 2 0 555 [[l PATENTED MAR 219m SHEET 1 SF 2 INVENTOR GERALD J. OT TAVAN ATTORNEYS.

] WE \TEUHAR 2 1971 SHEET 2 BF 2 INVENTOR GERALD J. OTTAVAN ATTORNEYS.

CONSTANT TENSION PAPER SUPPLY MECHANISM BACKGROUND OF THE INVENTION 1. Field of the Invention I The present invention relates to a paper supply mechanism, and especially to a paper supply mechanism for feeding pressure sensitive adhesive backed material to a label printing machine.

' 2. Description of the Prior Art Paper supply mechanisms for printing presses are well known. However, there has been difficulty encountered in the past in regulating the paper supply mechanisms to maintain constant tension on the paper, and such 'mechanisms rarely provide for means for indicating the value of tension.

SUMMARY OF THE INVENTION The improved paper supply mechanism of the present invention includes a self-adjusting brake which maintains substantially constant tension on the paper being fed by the mechanism by reducing the braking force on the paper concomitantly with the reduction in the inertia of the paper reel from which the paper is supplied. The paper supply mechanism further includes a simplified convenient means for indicating the degree of tension on the paper.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a side elevational view of the tension supply mechanism of the present invention in combination with a printing head for printing labels on the paper stock;

FIG. 2 is a top plan view of the constant tension paper feed; and

FIG. 3 is an end elevational view thereof.

DETAILED DESCRIPTION OF THE PREFERRED EM- BODIMENTS Referring now to the drawings in detail, the constant tension supply mechanism of the present invention is generally designated by the reference numeral 12. As shown herein, the supply mechanism 12 is for paper, here shown as label paper 14 of the pressure sensitive adhesive backed type. The constant tension mechanism 12 finds its preferred utility in a label printing machine or press which includes a printing head 16 of any desired construction. Also included are means 28 for advancing the paper stock 14 in a step-by-step motion. As here shown there are two means 28 interposed between the feed mechanism 12 and the printing head 16.

Each of the paper feed devices 28 may be powered off a common shaft if desired. The supply mechanisms include a feed or power roller 116 which rotates intermittently in response to an intermittent input means not shown. The axis of the power roller extends transversely of the direction of movement of the paper 14 and of a frame 62 which forms the basic support for the entire mechanism. Also secured to the frame 62 are a pair of upstanding supports 118 which supports are U-shaped in elevational view. Slidably mounted between legs 120 and 122 of U-shaped support 118 is a bearing block 123 on which is rotatably mounted an idler or pressure roller shaft 124. Extending across the tops 'of the legs 120 and 122 and secured thereto is a bar 126 having a threaded aperture 128 extending vertically therethrough. Threadedly mounted in the threaded aperture 128 is a manually adjustable screw 130 the bottom of which is in engagement with the bearing block 123. Mounted on the idler roller shafts are a pair of idler or pressure disc 132 of substantially identical diameter to the drive roller 116. The amount of pressure applied by the pressure discs 132 to the drive rollers 116 is adjustable by rotation of the adjustment screws 130 which move the idler shaft 124 vertically to move the idler discs 132 into tighter or less tight engagement.

With the structure of the supply mechanism 28 as described, it will be obvious that each time power roller 116 rotates, each of the drive mechanism 28 will operate to advance paper 14 sandwiched between the drive rollers 116 of the pressure discs 132 a predetermined amount which is adjustable by adjustment of the amount of rotation of drive roller 1 16. As indicated each of the paper feeding devices 28 is substantially identical in construction. However, there is one minor difference, namely the proportioning the parts. Specifically, the power rollers 116 of each of the supply mechanisms 28 are increasingly larger as the feeding device is located more remotely from the paper supply mechanism 12. This assures that the paper is always under slight tension as it moves away from the supply mechanism 12.

The supply mechanism 12 is primarily mounted on a horizontally extending cantilevered beam 144 that is secured to the base 62 of machine 10. Secured to the upper surface 146 or of beam 144 is a bearing block 148 in which is pivotally or rotatably mounted a shaft 150 to which is fixed a U-shaped member or'lever 152 that carries between its arms 154 and 156 a brake drum or roller 158. Fixed to U-shaped member 152 as by welding or suitable securing elements is a horizontally extending counterbalance arm 160 on which is disposed a counterbalance 162 which may be moved longitudinally of the counterbalance arm 160 and then releasably secured in a preferred position as by a setscrew 164. Also fixed to U- shaped member 152 as by welding or by suitable securing elements is an upstanding arm 166. Pivotally mounted at the upper end of the upstanding arm 166 is a bellcrank shaped member 167 the horizontal portion of which is a roller 168. Threadedly secured to the vertical portion 169 of member 167 is a thumb screw 171 which is adjustably threadedly secured to the upstanding arm 166. The horizontal positioning of roller 168 may be adjusted by operating the thumb screw 171 whereby to insure that there will be no side or lateral movement of the paper 14 as it moves off the reel and into the remainder of the machine 10. In addition, the member 167 and its associated parts play an important role in maintaining tension on the paper as it comes off the reel as will be described hereinafter. Cantilevered outwardly of the arm 154 of U-shaped member 152 is a rotatable shaft on which is mounted a spool comprising a hub 172, a first side disc 174 and a removable second side disc- 176, the roll of paper 178 being disposed on the spool 172 between the side discs 174 and 176. Connected by a bracket 178 to cantilever 144 is a brake member 180, preferably made of wood although other friction material may be employed, which brake member is provided with an arcuate braking surface 182 complementary to the brake drum 158 for reception thereof.

With the described brake, the amount of braking force applied between the brake drum 158 and the brake member 182 is a function of the weight of the reel of paper 178 and of the weight of the counterweight 162 and the position of the counterweight on the lever 160, Accordingly, by adjusting the position of the counterweight 162 on lever 160 at the outset of a run, the amount of tension on the paper can be established, as this will be a function of the braking force on the braking drum 158, and of the inertia of the paper reel 178. It will be seen that as paper is consumed from the reel 178, the amount of inertia of the reel will decrease. Concomitantly, the amount of braking force, which is dependent upon the weight of the reel, will also decrease and it has been found that these decreases tend to offset one another thereby to maintain a constant tension on the paper 14. In addition, it will be seen that if there is undue tension on thepaper as it moves off the reel 178, this tension will tend to act in a horizontal direction on the roller 168 whereby to pivot the arm 166 clockwise as its viewed in FIG. 5. This pivotal movement of arm 166 will tend to release the brake 158-180 whereby to reduce the tension on the paper in order to maintain a substantially constant tension thereon.

Mounted on cantilever 144 by a rotatable pin 184 is a lever 186 having a pair of rollers 188 and 190 on its free ends. Also secured to the rotatable pin 184 is a crank W2 the free end of which is secured to a tension spring 194 which is anchored at its other end to a fixed anchor 196 that is secured to the cantilever 144. Thus the spring 194 tends to rotate the crank 192 and hence the lever 186 in a counterclockwise direction. It will be seen that the tension on the paper 14 as it passes about rollers 188 and 190 will tend to rotate the lever 186 in a clockwise direction. By adjusting the tension of spring 194 as well as from braking force between brake drum 158 and brake 182, the lever 186 can be positioned substantially vertically. The substantially vertical positioning of lever 186 thereafter will indicate that the appropriate amount of tension is applied to paper 14.

In use, a reel 178 of label paper 14 is positioned on the spool 182 and is held there as by the affixing of the removable side plate 176. The paper is then lifted off the reel to cause the reel to rotate either clockwise or counterclockwise, (the supply mechanism 12 works just as well irrespective of the direction of removal of the paper 14) and thence over roller 168 and about roller 188 and roller 190, and then to an upward directional guide means comprising a roller 198 and two pairs of rollers 200 and 202 which are secured between a pair of brackets 204 fixed to the frame 62, and thence in tangential contact with a guide roller 206 and finally into the first feed mechanism 28 as described above. As the feed mechanism operates to advance paper 14 the paper will be stripped off the reel 172 and advance along the described path moving in the direction of the printer head 16.

While I have herein shown and described the preferred form of the present invention and have suggested modifications therein, other changes and modifications may be made rather than within the scope of the appended claims without departing from the spirit and scope of the invention.

I claim:

1. A constant tension feed mechanism comprising:

a. a support;

b. a lever pivotally mounted on said support at a fulcrum;

c. spindle means for rotatably mounting a reel of elongated material on one side of said lever;

d. brake means including a circular member rotatable with said spindle means and a stationary member having a surface in frictional engagement with the periphery of said circular member; and

e. counterbalance means connected to said lever and tending to rotate said lever in a direction opposite to the direction of rotation resulting from the weight of said spindle means.

2. The feed mechanism of claim 1, wherein said circular member is a brake drum fixed to said spindle, and said stationary member is a brake shoe and said surface thereof is complementary to the periphery of said brake drum.

3. The feed mechanism of claim 2, wherein said counterbalance means is a weight adjustably positionable on said lever on the other side of said fulcrum.

4. The feed mechanism of claim 3, further comprising a vertically extending lever pivotally mounted on said support, a pair of roller means, one of said pair of roller means mounted on said vertically extending lever on each side of the pivot thereof, and spring means for biasing said vertically extending lever to pivot in a direction that moves said upper roller means away from said spindle means.

5. The feed mechanism of claim 3, further comprising an arm secured to said lever and extending away therefrom, and a horizontal roller mounted on said arm.

6. The feed mechanism of claim 5, further comprising a vertically extending lever pivotally mounted on said support, a pair of roller means, one of said pair of roller means mounted on said vertically extending lever on each side of the pivot thereof, and spring means for biasing said vertically extending lever to pivot in a direction that moves said upper roller means away from said spindle means. 

1. A constant tension feed mechanism comprising: a. a support; b. a lever pivotally mounted on said support at a fulcrum; c. spindle means for rotatably mounting a reel of elongated material on one side of said lever; d. brake means including a circular member rotatable with said spindle means and a stationary member having a surface in frictional engagement with the periphery of said circular member; and e. counterbalance means connected to said lever and tending to rotate said lever in a direction opposite to the direction of rotation resulting from the weight of said spindle means.
 2. The feed mechanism of claim 1, wherein said circular member is a brake drum fixed to said spindle, and said stationary member is a brake shoe and said surface thereof is complementary to the periphery of said brake drum.
 3. The feed mechanism of claim 2, wherein said counterbalance means is a weight adjustably positionable on said lever on the other side of said fulcrum.
 4. The feed mechanism of claim 3, further comprising a vertically extending lever pivotally mounted on said support, a pair of roller means, one of said pair of roller means mounted on said vertically extending lever on each side of the pivot thereof, and spring means for biasing said vertically extending lever to pivot in a direction that moves said upper roller means away from said spindle means.
 5. The feed mechanism of claim 3, further comprising an arm secured to said lever and extending away therefrom, and a horizontal roller mounted on said arm.
 6. The feed mechanism of claim 5, further comprising a vertically extending lever pivotally mounted on said support, a pair of roller means, one of said pair of roller means mounted on said vertically extending lever on each side of the pivot thereof, and spring means for biasing said vertically extending lever to pivot in a direction that moves said upper roller means away from said spindle means. 